Answer:
If one wants to estimate the cost of living of an individual, then the factors such as salary, age, marital status, etc. are independent variables, while the cost of living of a person is highly dependent on such factors. Therefore, they are designated as the dependent variable.
Nature, in the broadest sense, is the natural, physical, material world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are part of nature, human activity is often understood as a separate category from other natural phenomena.[1]
<u>C. Interspecific competition</u> in ecology, is a form of competition in which individuals of different species compete for the same resources in an ecosystem (e.g. food or living space). This can be contrasted with interspecific cooperation, a type of symbiosis.
Answer:
<u>Biofilms are</u> defined as complex communities of microorganisms that grow embedded in a self-produced polymeric organic matrix and adhered to a living or inert surface, and that can present a single microbial species or a range of different species
Explanation:
The bacteria that form the biofilm are in what is called sessile form, exhibiting a phenotype different from those of the same cells in unicellular or free form (planktonic form) with respect to the growth rate and gene transcription (Donlan, 2002 ).
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The formation</u> of biofilms is an adaptive strategy of microorganisms, since growth in biofilm offers four important advantages: (I) protects microorganisms from the action of adverse agents, (II) increases the availability of nutrients for their growth, (III) facilitates the use of water, reducing the possibility of dehydration and (IV) enables the transfer of genetic material (DNA). All of these circumstances can increase your survival capabilities. As a consequence, <u>the usual methods of disinfection or the use of antibiotics are often ineffective against biofilm bacteria</u>.
In addition to the risk of contamination, the development of biofilms can interfere with different processes and cause damage to the equipment. In drinking water systems the formation of biofilms can obstruct the pipes reducing their speed and transport capacity causing an increase in energy consumption. The formation of biofilm in heat exchangers and cooling towers can reduce heat transfer and as a consequence its efficiency in the process. The formation of persistent biofilms on metal surfaces can cause corrosion due to acid production by bacteria.
